Drafting pen with cleansing vent valve stem



Dec. 8, 1970 E. BOK

` i DEAE-TINE PEN WITH cEEANsING VENT VALVE STEM Filed Dec. l1, 1968 04.../ flllrmlal.. hv

'United States Patent O Int. Cl. B43k 1/10 U.S. Cl. 401-259 Claims ABSTRACT OF THE DISCLOSURE Stylographic drafting pens of the type having a writing nib communicating with a vented ink reservoir via a capillary passage, particularly a vent valve stem reciprocably supported within the reservoir and at one end for the capillary passage and at the other end having a flange for cleansing dried ink from the vent valve area on top of the ink reservoir.

CROSS-REFERENCES TO RELATED APPLICATIONS Continuation-in-part of EXtendible-Retractible Pen Having Vent and Capillary Cleaning Means, Ser. No. 774,097, filed Nov. 7, 1968, now abandoned.

FIELD OF THE INVENTION Conventional stylographic drafting pens include a vent valve stern which is longitudinally reciprocable through the pen barrel vent valve and into the ink reservoir. However, such pens have no convenient means for cleansing the inevitably accumulated dried ink from the periphery of the vent valve. Also, such pens involve complex means for supporting the vent valve stem and the compression springs within the barrel.

SUMMARY OF THE INVENTION According to the present invention, the writing pen is comprised of a housing, ink reservoir, writing nib with its pen tip communicating with the ink reservoir via a capillary passage, a cleaning wire in this passage and a vent valve in the top part of the ink reservoir. Venting of this reservoir is possible by an upward moving of this vent valve to its top position.

An ink reservoir is located on top of the vent valve, providing a greater lateral surface than the vent valve itself. This ink remover rests upon the top of the ink reservoir, as the remover together with the vent valve is in its lowest position. The resting of the remover upon the vent valve keeps the vent opening periphery free from an excessive dried ink build-up, enabling a good venting of the ink reservoir as the vent valve is reciprocated longitudinally to its top position.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. l is a fragmentary vertical sectional view of the top of a stylographic writing pen with an inadequate venting of the ink remover part of it.

FIG. 2 is a vertical sectional view of a stylographic writing pen according to the invention, `showing an improved venting system of the ink chamber with the aid of a vent stem which is shown in its rest position.

FIG. 3 is an enlarged vertical sectional view of the writing pen according to FIG. 2, showing the vent stem in its lowest or extended position.

FIG. 4 is an enlarged vertical sectional view of the writing pen according to FIGS. 2 and 3, showing the vent stem in its top or retracted position.

Patented Dec. 8, 1970 ICC DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1 the top part of a writing pen 110 with poor air venting is shown, in which pens the vent stem 122 longitudinally is displaceable by means of knob 134, which knob is an extension of vent stem 122. Knob 134 protrudes through the opening 182 in cover 180.

The vent valve 158 as part of the vent stem 122 is longitudinally movable in the vent opening 162. After a longer period of time dried ink 188 is built up in the collector chamber 184, which dried ink is the result of the escaping of ink through the vent opening 162 during the venting of the barrel 112.

Specially, if the vent stem 122 automatically under spring pressure is moved upwards from its lowest position to its top position (FIG. 4) and thereafter downwards t0 its rest position (FIG. 2), there is a time limit for the venting, which limit normally is a fraction of a second. This layer 188 of dried ink then may result in an inadequate venting due to the shortened time of venting, as during the up and downward movement of the stem 122. In such case, only the upper part of the passageway 158 of stem 122 is available for venting.

In FIG. 2 a writing pen 10 is shown with an improved vent system. This pen 10 mainly consists of barrel 12, which also serves as the ink reservoir for the ink 14, writing nib 16 and pen tip 18. Cleaning wire 20, which extends through pen tip 18, is an integral extension of vent stem 22.

Lower compression spring 24 is positioned in the lower part of barrel 12 in between writing nib 16 and spring base 26 of the vent stern 22. Top compression spring 28 is located in the top of barrel 12 in between spring base 30 of vent stem 22 and the barrel top 32 and provides together with the lower compression spring 24 the longitudinally balanced rest position of the vent stem 22 (FIG. 2) so long as no longitudinally compressive forces are applied on this vent stern 22 via knob 34, protruding through barrel 12.

Writing nib 16 is by means of screw thread 36 leak free attached to barrel 12, providing a lock for vent stem 22 and compression springs 24 and 28 after assembly of the pen.

The longitudinally separated spring bases 26 and 30 also serve as a guidance means for the vent stem 22, as their bases during the longitudinal displacement of the vent stem move along the inside wall 40 of the barrel 12, enabling the vent stem 22 to have small lateral dimensions and to be constructed of synthetic material.

For filling barrel 12 with ink the side wall 48 of the barrel 12 is provided with opening 50. A milled filler ring 52, which manually is rotatable within the recess 54 of the barrel 12, normally provides a sealing olf of the opening 50. However, if the filler opening (not illustrated) of filler ring 52 is rotated from the sealing position to register with opening 50, the lling of barrel 12 with ink 14 is possible.

The top part 58 of vent stem 22 serves as a vent valve, whereby the knob 34 as an extension is van integral part of this valve 58. This valve 58 is movable through the vent opening 62, see also FIG. 4.

Recess or vent 66 in the vent stem of the valve 58 provides venting of the air column 68 above the ink column 70 in the writing pen 10. This venting takes place as vent 3 stem 22 is brought to or near its top position, as is shown in FIG. 4.

This top position of the vent stem 22 is achieved by downward moving of the vent stem 22, to its lowest portion (FIG. 3) by hand via knob 34 against the force of the strong compression spring 24, then suddenly releasing knob 34. The vent stem 22 then moves under the force of spring 24 upwards to its top position (FIG. 4).

Barrel 12 is provided with a barrel cap 80 with screw thread attachment 81. Knob 34 is covered with the bushing 60. Thus, bushing 60 longitudinally protroudes through this barrel cap 80. The barrel cap 80 supplies an extra guidance to vent stem 22 and the stem valve 58 is protected against exterior damage. Furthermore, it is impossible for ink, which during the venting operation has escaped through the vent opening 62, to escape the collector chamber 84. The small lateral opening 86 in this cap 80 thereby serves for the air venting. Cleaning of the chamber 84 is easy by unscrewing the cap 80 from the barrel 12.

The bushing 60 has a loose fitting connection with vent stem 22. This bushing 60 has on its open end the ring shaped edge 90 which is deformed so as to provide a nonat or rilled surface 92, see also FIGS. 4 and 5.

By moving the bushing 60 downward, as is indicated in FIG. 3 the bushing surface 92 comes to a rest against the top 94 of the barrel 12. By thereafter rotating the bushing 60, formed dried ink on top 94 is scraped off from this top 94 by means of bushing 94 and collected in chamber 84 for periodical removal. A clean top surface 94, also after a long period of use of the writing pen is thus achieved with good air venting.

In the FIG. 7 modification knob 34 as part of stem holder 98 protrudes laterally through the opening 100 in side wall 102 0f barrel 12 and whereby the bottom part 104 of this holder 98 comes to a rest against the top 106 of the ink reservoir 108, if the knob 34 is forced downwards to its lowest position.

Also here the bottom part 104 prevents the build up of dried ink close to the vent opening 60, so that if the knob 34 is moved to its top position no clogged ink can prevent air venting of ink reservoir 108.

I claim:

1. In a drafting pen of the type having a barrel with ink reservoir, a vent valve opening in the reservoir, and

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4 a writing nib secured to the bottom of said barrel and communicating with said reservoir via a capillary passage:

(A) a vent valve stem reciprocably extending into said vent valve opening and having a laterally extending cover portion abutting the top of said vent valve, so as to engage and dislodge accumulated dried ink.

2. A drafting pen as in claim 1, said vent valve stem being laterally rotatable within said barrel and said cover portion being laterally extending and offset with respect to the stem end and said cover portion substantially covering the vent valve top periphery.

3. A drafting pen comprising:

(A) a barrel with ink reservoir, having a vent valve opening at its top;

(B) a pen tip secured to the bottom of said barrel and having a writing nib communicating with said reservoir via a capillary passage;

(C) a vent valve stem reciprocably extending through said vent valve opening and into said reservoir and having:

(i) a laterally extending portion abutting the top of said vent valve;

(ii) laterally extending spring base members engaging the interior wall of said barrel and medially interposed between a top compression spring and a bottom compression spring, supported at opposite ends of said reservoir beneath said vent valve.

4. A drafting pen as in claim 3, including:

(D) a cap with air vent connected to the barrel top and peripherally encompassing said valve stem top extending axially therethrough.

5. A drafting pen as in claim 4, said cap being threadedly engagable with said barrel top and including a lateral vent.

References Cited UNITED STATES PATENTS 1,447,632 3/ 1923 Schmidt 401-258 FOREIGN PATENTS 1,073,878 6/1967 Great Britain 401-259 597,184 8/1959 Italy 401-259 LAWRENCE CHARLES, Primary Examiner 

